Piston



(No Model.) I 2 Sheets-Sheet 1. E. F. PEAUOCK.

PISTON.

10.582763 Patented May 18, 1897.

UNITED STATES PATENT GEErCE.

EDIVARD F. PEACOCK, OF PHILADELPHIA, PENNSYLVANIA.

msToN.

SPECIFICATION forming part of Letters Patent No. 582,763, dated May 18,1897.

` Application filed .Tuly 17,1895. Serial No. 556.258. (No model.)

To all whom, t may concern:

Be it known that I, EDWARD F. PEAcooK, a citizen of the United States,residing at Philadelphia, in the county of Philadelphia and State ofPennsylvania, haveinvented certain new and useful Improvements inPistons; and I do declare the following to be a full,clear,and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same, reference being hadto the accompanying drawings, and to the letters of reference markedthereon, which form a part of this specification.

My invention relates to steam-engines; and it consists in certainimprovements in pistons.

The usual mode of connecting a piston to the rod is to provide'thepiston with a heavy central boss in which is bored a slightly-taperinghole to `fit a similar taper on the end of the piston-rod. The piston iseither shrunk on the rod or is held by nuts screwed upon a threaded neckon the end of the rod. This construction has some objections, since thepiston is apt to work loose or the rod to break off at the shoulder whenit enters the piston. In any event the piston must be heavy in order tobe strong.

My invention aims to obviate these difliculties and provide a strong,rigid, but light connection for the piston and piston-rod. I also aim toimprove the construction of the bull-rin gs and packing-rin gs,especially when used in connection with my break joint blocks shown anddescribed in my Patent No. 407,370, dated July 23, 1889.

In the accompanying drawings,Figure l is a sectional plan view on line ll, Fig. 2, of a piston embodying myimpro vements. Fig. 2 is an axialsection of the same on line 2 2, Fig. 1. Figs. 3 and 4. show two formsof break-joint block used with this piston. Fig. 5 is a modification.Fig. Gis a further modiiication. Fig. 7 is a third form of break-jointblock, and Fig. S is a modification thereof.,

The pistonerod A is preferably hollow .for the sake of lightness, andthus made may be made of somewhat greater diameter than usual to givegreater strength without increase in weight. Near its end it is providedwith an integral flange ct of considerable diameter, to which isattached, preferably by rivets B, the back plate C of the piston. Thisplate may be plain, as shown in Fig. 6, bntI prefer to form it with arimC near its outer edge, having a cylindrical outer face and providedat intervals with internal bosses c', in which are drilled holes whichare tapped to receive the screws D, by means of which the follower-plateE is secured in place. A central screw D' may enter the end of the rod Athrough the plate F., and the plate may be recessed at c to receive theend of the rod. It will be noticed that by this construction Idispenseentirely with the heavy central hub or boss of the piston andform a light, hollow, but strong structure iirnily secured together. Theedge of the follower-plate E projects beyond the flange C', and inconnection therewith and with the projecting edge c of the plate O formsa wide peripheral groove in which are received the bull-ringsF FQpreferably three in number, as shown. The two outer rings F are rabbetedto form a packing-ring groove, which is filled by a thin packing-ring G,sprun g into place as usual. Y

The ends of the rings G do not meet,but the space between them is filledby a breakjoint block II, seated in a slot in the bull-rin g. In myprior patent I have shown the block seated in a recess or pocket formedat one side of the ring-groove,with a rib on the block projecting intothe space between the ends of the packing-ring. The pocket is difficultand expensive to make, so I have improved upon that construction byslotting the bull-ring clear across. This construction is one which canbe easily and quickly effected on a slotting or milling machineand'materially reduces the cost. The slot may extend below the bottom ofthe ring-groove, as shown in Figs. 1 and 3, or it may be iiushtherewith, as in Fig. 4.. In the former case the break-joint block notonly fills vthe slot in the bull-ring and has a rib 7L to t between theends of the packing-ring and keep it from revolving in its groove, butthere are also flanges 7L on the block to underlie the ends of thepacking-ring and form a better break-joint. The bullrings may be looseon the rim C', but they are preferably kept from revolving on the pistonby means of a dowel-pin I, passing through the follower-plate E, allthree of the rings, and into the plate C. This pin may be screwthreaded,as shown in Fig. 2, or it may be in the form of a rivet having shouldersz' to re- IOC:

ceive the plate C and follower E, through which pass necks i', which areheaded down, as shown in Fig. 6. The advantage of this construction isthat if a rivet breaks it cannot fall and make mischief in the cylinder.It will be noticed that these rivets also take the place of the screws Din Fig. 2.

Instead of using three bull-rings side by side, I may have but one, asshown at K, Figs. 4c, 7, and 8. This is provided with perforated bossesk 011 the inside for the rivets I, and its edges are rabbeted, as shownin Fig. 7, to form packing-ring grooves. The ring is also slottedthrough on each edge to receive a break-joint block H, which is of' thesame depth a-s the ring and preferably engages a shallow recess at 71;'to keep it in place, or the block may be of the same width as thegroove, as shown in Fig. 8. The two blocks on the opposite edges of thering are preferably placed out of line with each other. If desired, aspring L maybe placed in a pocket 7a2 in the ring to force the blockoutwardly against the inner surface of the cylinder. This is moreespecially necessary in vertical cylinders, since in horizontalcylinders the weight of the block keeps it out, the joint being arrangedat the bottom or lower side of the piston.

It will be observed that all the break-joint block-s shown are of thesame thickness as the bull-ring, so as to fill the slot therein when inplace.

Considerable attention is now being given to the problem of reducing theweight of the reciprocating parts in locomotives and othersteam-engines, and an important advantage of my construct-ion of pistonis that I can use light materials, such as steel and phosphorbronze, inplace of cast-iron. The bull-rings especially should be made ofantifriction metal to insure the smooth wearing of the cylinder, whilethe packing-rings may be of cast-iron, asheretof'ore; but being narrowand thin they will be likely to avoid any injurious cutting.

Should it be desirable to use metal for the back plate andfollower-plate which is not suitable to come in contact with thecylinder, the plates can be slightly reduced in diameter, as indicatedby dotted lines in Fig. G.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is-

l. The combination with a plate-piston, of a forged piston-rod havingnear one end an integral and comparatively thin fiange considerablylessin diameter than the plate-piston, to which it is designed to beattached, substantially as described.

2. The combination with a forged hollow piston-rod having near one endan integral and comparatively thin flange of a plate-piston of greaterdiameter than and attached to said flange, substantially as described.

3. The combination with a piston-rod having near one end an integralfiange, of a piston-plate riveted to said flange, substantially asdescribed.

4. The combination with a hollow pistonrod having near one end anintegral flange, of a piston-plate overlapping said flange and securedthereto by rivets lying parallel with said rod, substantially asdescribed.

5. The combination with a piston-rod having near one end an integralflange, of a piston having a back plate overlapping and sccured to saidflange, and a follower-plate secured to the end of the rod, and one ormore bull-rings fitting between said plates, substantially as described.

G. The combination with a piston-rod having an integral flange, of aback plate riveted to said flange, a follower-plate secured to the endof said rod, one or more bull-rings fitting between said plates, and apin passing through said plates and rings to keep the latter in place,substantially as described.

7. In a piston, a back plate having a cylindrical rim provided withinternal bosses, a follower-plate, screws passing through said plateinto tapped holes in said bosses, bullrings fitting around said rim, anda dowelpin passing through said plates and rings, substantially asdescribed.

S. In a piston, the combination with a bullring having a packing-ringgroove, and a slot ext-ending elearacross said bull-ring, andintersecting said groove, of a packing-ring in said groove, and abreak-joint block received in said slot, substantially as described.

9. In a piston, the combination with a bullring rabbeted on one edge toform a packingring groove and having a slot extending clear through saidbull-ring and intersecting said rabbet, ot' a packing-ring in saidgroove, and a break-joint block received in said slot, substantially asdescribed. I

l0. The combination with a bull-ring having a packing-ring groove and aslot extending clear through said bull-ring, of a paekin gring in saidgroove and a break-joint block as thick as the lnull-ring andfittingsaid slot, substantially as described.

l1. The combination with a bull-ring having a packing-ring groove and aslot extending clear through said bull-ring, of a breakjoint block ofthe same thickness as the bullring and fitting said slot, t-he blockbeing provided with a rib to enter between the ends of the packing-ring,substantially as described.

12. The combination with a bull-ring having a packing-ring groove and aslot extending clear through the ring, of a break-joint block II fittingsaid groove, and having a rib 71, to enter between the ends of thepackingring, and flanges 71. to underlie the ends of said ring,substantially as described.l

In testimony whereof I affix my signature in presence of two Witnesses.

EDVARD F. PEACOCK.

\Vitnesses:

GEORGE H. JAcKsoN, LUTHER WALKER.

IIC

